SHALLOW SEISMIC SURVEY IN THE AREA PETARO-HYDERABAD

Abstract

A project of shallow seismic refraction was carried o ut in PETARO-HYDERABAD ( SINDl for the completion of d isserta tion requirements. The DurDose of the survey was to e s tablis h v e locity-lithology re lationship,to determine the thickness of different subsurface layers and to trace the nature of r efract o r boundar ies. To achieve this , true velocities , depths and dip angles were obtain ed from TX-graph. Thes e graphs and calculations were prepared manually as well as on the computer by using FORTRAN-7 7 data processing programme besides using HP-seisrnic r efracti on softwar e . The nature of refractor b0undary was mapped b y HAWKIN ' S METHOD. The interpretation of seismic data shows two lavers having; velocities Vo and VI respectively. I Velocity of first layer r a nges from 380 m/sec to 540 m/s e~ wher e as, thickness of this layer ranges from 8.2 m to 12.3 m. Th e ve l ocity range of this layer indicates a lithology of Alluvium. Th e v e l oc ity of second layer ranges from 1620 m/sec to 17 8 0 m/sec. Th e velocity range of this l ayer is indicati.ve of subweathered sailor wea ther e d sandstone.